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Scientific Publications

Boehringer Ingelheim offers an overview of scientific publications on the following pages. This overview represents all publications of the last three years (YTD) where employees of Boehringer Ingelheim worldwide were involved.

Selective CB2 receptor agonists. Part 3: The optimization of a piperidine-based series that demonstrated efficacy in an in vivo neuropathic pain model

Source:

Bioorg Med Chem Lett Article in Press (2015)

Abstract:

A novel class of potent cannabinoid receptor 2 (CB2) agonists based on a (S)-piperidine scaffold was identified using ligand-based pharmacophore models. Optimization of solubility and metabolic stability led to the identification of several potent CB2 agonists (e.g., 30) that displayed selectivity over cannabinoid receptor 1 (CB1) and acceptable drug like properties. In rats, compound 30 demonstrated a favorable pharmacokinetic profile and efficacy in a Streptozotocin-induced diabetic neuropathy model, with full reversal of mechanical hyperalgesia.

Objective To examine the prevalence of chronic kidney disease (CKD) and related cardiovascular morbidity in a cross-sectional population in patients with type 2 diabetes (T2D) treated in a primary care setting in Finland. Research design and methods Data were collected and recorded from 42 primary care centres, which recruited 629 patients diagnosed with type 2 diabetes (T2D) to this non-interventional study. Data including patient characteristics, kidney function and albuminuria, blood pressure, HbA1c, lipid and lipoprotein levels, and diabetes duration as well as current medication was collected in each patient. Results In the final study population of 625 patients, the mean age was 67 years (range 29-92 years), BMI 32.8 kg/m2 (95% CI 32-33), blood pressure 142/80 mmHg (140-143/80-81) and HbA1c 7.1% (7.0-7.2) (53.8 mmol/mol, 53-55) and the median duration of diabetes was 9.2 years ranging from newly diagnosed to 43 years. History of dyslipidemia had in 73.3% of patients, 27.8% had cardiovascular disease and 82.7% had hypertension. The primary endpoint, prevalence of CKD of any grade (1-5) or albuminuria, was 68.6%. Regarding declined renal function, 16.2% of patients had an estimated glomerular filtration rate (eGFR) &lt;60 ml/min/1.72 m2, classifying as CKD 3-5. Only one patient was within CKD5. Regarding renal damage, albuminuria was present in 24.3% of patients, with microalbuminuria in 17.1% and macroalbuminuria in 7.2%, respectively. Combining the patients with CKD 3-5 and/or the presence of albuminuria, 34.7% seemed to suffer from significant CKD. The proportion of patients with albuminuria increased with a decrease in glomerular filtration rate. Historically, diabetic nephropathy had been diagnosed in 24.3% of the patients. Conclusions Nearly 70% of patients with T2D treated in primary care in Finland have some sign of CKD and nearly half of all T2D patients have a significant CKD. However, only half of the latter had it diagnosed and documented in their patient charts, thus highlighting the importance of performing routine screening of nephropathy by measuring both albuminuria and eGFR in patients with T2D. Prevention of this complication with active therapy for risk factors, such as hypertension and dyslipidemia is warranted.

Virtually all diabetic dogs require exogenous insulin therapy to control their hyperglycaemia. In the UK, the only licensed insulin product currently available is a purified porcine insulin preparation. Recombinant insulin is somewhat problematic in terms of its manufacture, since the gene product (preproinsulin) undergoes substantial post-translational modification in pancreatic . cells before it becomes biologically active. The aim of the present study was to develop recombinant canine single chain insulin (SCI) analogues that could be produced in a prokaryotic expression system and which would require minimal processing. Three recombinant SCI constructs were developed in a prokaryotic expression vector, by replacing the insulin C-peptide sequence with one encoding a synthetic peptide (GGGPGKR), or with one of two insulin-like growth factor (IGF)-2 C-peptide coding sequences (human: SRVSRRSR; canine: SRVTRRSSR). Recombinant proteins were expressed in the periplasmic fraction of Escherichia coli and assessed for their ability to bind to the insulin and IGF-1 receptors, and to stimulate glucose uptake in 3T3-L1 adipocytes.All three recombinant SCI analogues demonstrated preferential binding to the insulin receptor compared to the IGF-1 receptor, with increased binding compared to recombinant canine proinsulin. The recombinant SCI analogues stimulated glucose uptake in 3T3-L1 adipocytes compared to negligible uptake using recombinant canine proinsulin, with the canine insulin/cIGF-2 chimaeric SCI analogue demonstrating the greatest effect. Thus, biologically-active recombinant canine SCI analogues can be produced relatively easily in bacteria, which could potentially be used for treatment of diabetic dogs.

Synthesis of empagliflozin, a novel and selective sodium-glucose co-transporter-2 inhibitor, labeled with carbon-14 and carbon-13

Source:

J Label Compd Radiopharm 57 (12), 687-694 (2014)

Abstract:

Empagliflozin, (2S,3R,4R,5S, 6R)-2-[4-chloro-3-[[4-[(3S)-oxolan-3-yl]oxyphenyl]methyl]phenyl]-6-(hydrox ymethyl)oxane-3,4,5- triol was recently approved by the FDA for the treatment of chronic type 2 diabetes mellitus. Herein, we report the synthesis of carbon-13 and carbon-14 labeled empagliflozin. Carbon-13 labeled empagliflozin was prepared in five steps and in 34% overall chemical yield starting from the commercially available a-D-glucose-[13C6]. For the radiosynthesis, the carbon-14 atom was introduced in three different positions of the molecule. In the first synthesis, Carbon-14 D-(+)-gluconic acid .-lactone was used to prepare specifically labeled empagliflozin in carbon-1 of the sugar moiety in four steps and in 19% overall radiochemical yield. Carbon-14 labeled empagliflozin with the radioactive atom in the benzylic position was obtained in eight steps and in 7% overall radiochemical yield. In the last synthesis carbon-14 uniformly labeled phenolwas used to give [14C]empagliflozin in eight steps and in 18% overall radiochemical yield. In all these radiosyntheses, the specific activities of the final compounds were higher than 53 mCi/mmol, and the radiochemical purities were above 98.5%.

Progressive deterioration of pancreatic .-cell function in patients with type 2 diabetes mellitus (T2DM) contributes to worsening of hyperglycaemia. To investigate the effects of the dipeptidyl peptidase-4 inhibitor linagliptin on .-cell function parameters, a pooled analysis of six randomized, 24-week, placebo-controlled, phase 3 trials of 5mg of linagliptin daily was performed in 2701 patients with T2DM (linagliptin, n=1905; placebo, n=796). At week 24, observed improvements in HbA1c, fasting plasma glucose, and 2-h postprandial glucose were significantly greater for linagliptin than placebo (all p<0.0001). Homeostasis model assessment (HOMA)-%., as a surrogate marker of fasting .-cell function, was significantly improved with linagliptin, and did not change with placebo (placebo-adjusted mean±s.e. change for linagliptin: 16.5±4.6 (mU/l)/(mmol/l); p=0.0003). Further study is required to determine if the significant improvement in HOMA-%. with linagliptin will translate into long-term improvements in .-cell function.

Purpose: Long duration of type 2 diabetes mellitus (T2DM) is associated with progressive .-cell loss and may pose a challenge to maintenance of good glycemic control. This study aimed to assess the efficacy and safety of the dipeptidyl peptidase-4 inhibitor linagliptin in an understudied population of patients with long-standing T2DM. Methods: Data from 202 individuals with T2DM for &gt;10 years were pooled from 2 randomized, placebo-controlled, Phase III trials. Participants received either linagliptin 5 mg once daily (n = 122) or placebo (n = 80) for 24 weeks as an add-on to their current glucose-lowering therapy. Findings: Long-standing T2DM was associated with older age (mean [SD], 69.1 [10.0] years) and a high prevalence of diabetes-related complications (78% with diabetic kidney disease and 83% with macrovascular disease). The mean baseline glycosylated hemoglobin (HbA1c) level was 8.22% (1.08%), and mean baseline fasting plasma glucose level was 161.8 (49.2) mg/dL. Linagliptin significantly improved glycemic control after 24 weeks, with a placebo-adjusted mean change in HbA1c from baseline of -0.66% (95% CI, -0.95 to -0.38; P &lt; 0.0001). This change was accompanied by a significant reduction in fasting plasma glucose, with a placebo-adjusted mean change from baseline of -15.5 mg/dL (95% CI, -29.6 to -1.3; P = 0.0323) at week 24. Overall, linagliptin was well tolerated, with drug-related adverse events in 21.3% and 16.3% of the linagliptin and placebo groups, respectively. Investigator-reported hypoglycemia occurred more often with linagliptin (25.4%) compared with placebo (12.5%). However, no severe hypoglycemic events were reported with linagliptin. Moreover, in patients not receiving concomitant sulfonylureas, the incidence of hypoglycemia with linagliptin (12.5%) was similar to that with placebo (12.2%). Patients' mean weight remained unchanged in both groups. Implications: This pooled analysis found that linagliptin was well tolerated and significantly improved hyperglycemia in a clinically challenging population of patients with long-standing T2DM (&gt;10 years). Although T2DM is commonly associated with diminished .-cell function, the extent of glucose lowering was similar to that in linagliptin trials, which largely included patients in earlier stages of the disease. Thus, this observation supports the hypothesis that regulation of glucagon release from pancreatic beta cells may be of particular relevance for improving hyperglycemia in patients with long-term T2DM (NCT01194830 and NCT01084005).

Linagliptin improved glycaemic control without weight gain or hypoglycaemia in patients with Type 2 diabetes inadequately controlled by a combination of metformin and pioglitazone: A 24-week randomized, double-blind study

Source:

Diabetic Med 31 (12), 1505-1514 (2014)

Abstract:

Aims: To investigate the efficacy and safety of the dipeptidyl peptidase-4 inhibitor linagliptin in patients with Type 2 diabetes mellitus inadequately controlled by a combination of metformin and pioglitazone. Methods: This was a multi-centre, phase 3, randomized, double-blind, placebo-controlled study comparing linagliptin 5 mg once daily (n = 183) and placebo (n = 89) as add-on to metformin and pioglitazone. The primary endpoint was the change from baseline in glycated haemoglobin (HbA1c) after 24 weeks. Results: The placebo-corrected adjusted mean (se) change in HbA1c from baseline to 24 weeks was -6 (1) mmol/mol [-0.57 (0.13)%] (P < 0.0001). In patients with baseline HbA1c . 53 mmol/mol (7.0%), 32.4% of patients in the linagliptin group and 13.8% in the placebo group achieved HbA1c < 53 mmol/mol (7.0%) (odds ratio 2.94; P = 0.0033). The placebo-corrected adjusted mean (se) change from baseline in fasting plasma glucose at week 24 was -0.57 (0.26) mmol/l [-10.4 (4.7) mg/dl] (P = 0.0280). The incidence of serious adverse events was 2.2% with linagliptin and 3.4% with placebo. Investigator-defined hypoglycaemia occurred in 5.5% of the linagliptin group and 5.6% of the placebo group. No meaningful changes in mean body weight were noted for either group. Conclusions: Linagliptin as add-on therapy to metformin and pioglitazone produced significant and clinically meaningful improvements in glycaemic control, without an additional risk of hypoglycaemia or weight gain (Clinical Trials Registry No: NCT 00996658

Linagliptin improved glycaemic control without weight gain or hypoglycaemia in patients with Type 2 diabetes inadequately controlled by a combination of metformin and pioglitazone: A 24-week randomized, double-blind study

Source:

Diabetic Med 31 (12), 1505-1514 (2014)

Abstract:

Aims: To investigate the efficacy and safety of the dipeptidyl peptidase-4 inhibitor linagliptin in patients with Type 2 diabetes mellitus inadequately controlled by a combination of metformin and pioglitazone. Methods: This was a multi-centre, phase 3, randomized, double-blind, placebo-controlled study comparing linagliptin 5 mg once daily (n = 183) and placebo (n = 89) as add-on to metformin and pioglitazone. The primary endpoint was the change from baseline in glycated haemoglobin (HbA1c) after 24 weeks. Results: The placebo-corrected adjusted mean (se) change in HbA1c from baseline to 24 weeks was -6 (1) mmol/mol [-0.57 (0.13)%] (P < 0.0001). In patients with baseline HbA1c . 53 mmol/mol (7.0%), 32.4% of patients in the linagliptin group and 13.8% in the placebo group achieved HbA1c < 53 mmol/mol (7.0%) (odds ratio 2.94; P = 0.0033). The placebo-corrected adjusted mean (se) change from baseline in fasting plasma glucose at week 24 was -0.57 (0.26) mmol/l [-10.4 (4.7) mg/dl] (P = 0.0280). The incidence of serious adverse events was 2.2% with linagliptin and 3.4% with placebo. Investigator-defined hypoglycaemia occurred in 5.5% of the linagliptin group and 5.6% of the placebo group. No meaningful changes in mean body weight were noted for either group. Conclusions: Linagliptin as add-on therapy to metformin and pioglitazone produced significant and clinically meaningful improvements in glycaemic control, without an additional risk of hypoglycaemia or weight gain (Clinical Trials Registry No: NCT 00996658).

Objective: Obesity-related glomerulopathy is characterized initially by glomerular hyperfiltration with hypertrophy and then development of proteinuria. Putative mechanisms include endothelial dysfunction and filtration barrier injury due to oxidant stress and immune activation. There has been recent interest in targeting dipeptidyl peptidase 4 (DPP4) enzyme due to increasing role in non-enzymatic cellular processes. Methods: The Zucker obese (ZO) rat (aged 8 weeks) fed a normal chow or diet containing the DPP4 inhibitor linagliptin for 8 weeks (83 mg/kg rat chow) was utilized. Results: Compared to lean controls, there were increases in plasma DPP4 activity along with proteinuria in ZO rats. ZO rats further displayed increases in glomerular size and podocyte foot process effacement. These findings occurred in parallel with decreased endothelial stromal-derived factor-1alpha (SDF-1alpha), increased oxidant markers, and tyrosine phosphorylation of nephrin and serine phosphorylation of the mammalian target of rapamycin (mTOR). DPP4 inhibition improved proteinuria along with filtration barrier remodeling, circulating and kidney tissue DPP4 activity, increased active glucagon like peptide-1 (GLP-1) as well as SDF-1alpha, and improved oxidant markers and the podocyte-specific protein nephrin. Conclusions: These data support a role for DPP4 in glomerular filtration function and targeting DPP4 with inhibition improves oxidant stress-related glomerulopathy and associated proteinuria.

Transporter gene knockout rat models are attracting increasing interest for mechanistic studies of new drugs as transporter substrates or inhibitors in vivo. However, limited data are available on the functional validity of such models at the blood-brain barrier. Therefore, the present study evaluated Mdr1a [P-glycoprotein (P-gp)], Bcrp, and combined Mdr1a/Bcrp knockout rat strains for the influence of P-gp and breast cancer resistance protein (BCRP) transport proteins on brain penetration of the selective test substrates [14C]WEB 2086 (3-[4-(2-chlorophenyl)-9-methyl-6H-thieno[3,2-f][1,2,4] triazolo-[4,3-a][1,4]-diazepin-2-yl]-1-(4-morpholinyl)-1-propanon) for P-gp and dantrolene for BCRP. Brain-to-plasma concentration ratios (BPR) were measured after intravenous coinfusions of 5.5 mmol/kg per hour [14C]WEB 2086 and 2 mmol/kg per hour dantrolene for 2 hours in groups of knockout or wild-type rats. Compared with wildtype controls, mean BPR of [14C]WEB 2086 increased 8-fold in Mdr1a knockouts, 9.5-fold in double Mdr1a/Bcrp knockouts, and 7.3-fold in zosuquidar-treated wild-type rats, but was unchanged in Bcrp knockout rats. Mean BPR of dantrolene increased 3.3-fold in Bcrp knockouts and 3.9-fold in double Mdr1a/Bcrp knockouts compared with wild type, but was unchanged in the Mdr1a knockouts. The human intestinal CaCo-2 cell bidirectional transport system in vitro confirmed the in vivo finding that [14C]WEB 2086 is a substrate of P-gp but not of BCRP. Therefore, Mdr1a, Bcrp, and combined Mdr1a/Bcrp knockout rats provide functional absence of these efflux transporters at the blood-brain barrier and are a suitable model for mechanistic studies on the brain penetration of drug candidates. Copyright

Cynomolgus monkey as a surrogate for human aldehyde oxidase metabolism of the EGFR Inhibitor BIBX1382

Source:

Drug Metab Dispos 42 (10), 1751-1760 (2014)

Abstract:

BIBX1382 was an epidermal growth factor receptor inhibitor under clinical investigation for treatment of cancer. This candidate possessed an attractive preclinical absorption, distribution, metabolism, and excretion profile, yet failed in clinical studies due in part to poor oral exposure, resulting from extensive metabolism by aldehyde oxidase (AO). In vitro metabolism studies were performed in liver cytosol and cryopreserved hepatocytes frommultiple species. In addition, a pharmacokinetic study was performed in cynomolgus monkey for comparison with the reported human pharmacokinetics of BIBX1382. Estimated hepatic clearance of BIBX1382 in rhesus (42 ml/min per kg) and cynomolgus monkey (43 ml/min per kg) liver cytosol was comparable to human (.93% of liver blood flow). Metabolite identification after incubation of BIBX1382 in liver cytosol fortified with the AO inhibitor raloxifene confirmed that AO is involved in the formation of the predominant metabolite (BIBU1476, M1) in cynomolgus monkey. After intravenous and oral administration of BIBX1382 to cynomolgusmonkeys, high plasma clearance (118 ml/min per kg) and low oral exposure (Cmax= 12.7 nM and 6% oral bioavailability) was observed, with the exposure of M1 exceeding BIBX1382 after oral dosing. This pharmacokinetic profile compared favorably with the human clinical data of BIBX1382 (plasma clearance 25-55 ml/min per kg and 5% oral bioavailability). Thus, it appears that cynomolgus monkey represents a suitable surrogate for the observed human AO metabolism of BIBX1382. To circumvent clinical failures due to uncharacterized metabolism by AO, in vitro studies in the appropriate subcellular fraction, followed by pharmacokinetic and toxicokinetic studies in the appropriately characterized surrogate species should be conducted for substrates of AO. Copyright

Linagliptin improved glycaemic control without weight gain or hypoglycaemia in patients with Type 2 diabetes inadequately controlled by a combination of metformin and pioglitazone: A 24-week randomized, double-blind study

Combination of the sodium-glucose cotransporter-2 inhibitor empagliflozin with orlistat or sibutramine further improves the body-weight reduction and glucose homeostasis of obese rats fed a cafeteria diet

Sulphonylureas (SUs) are oral anti-diabetic drugs (OADs) that were introduced more than 60 years ago. Clinicians are familiar with their use and they remain extensively used. However, the SU class is associated with adverse effects of weight gain and hypoglycaemia. In addition, their effects on cardiovascular events remain contentious. Newer classes of anti-diabetic agents have been developed and these agents are weight neutral (di-peptidyl peptidase IV inhibitors), while others reduce weight (glucagon-like peptide analogues and sodium glucose co-transporter inhibitors). Furthermore, the newer agents are less likely to cause hypoglycaemia and have a potentially better cardiovascular safety profile. However, the newer agents are more costly than SUs and their long-term safety is unknown. It is therefore likely that SUs will continue to be used, and more so in resource-limited settings. One may mitigate the adverse effects of weight gain and hypoglycaemia associated with the SU class by using members within this class that are less probable to cause these adverse effects. Furthermore, the specific SU must be used at the lowest effective therapeutic dose. In patients at high risk of SU-induced hypoglycaemic episodes (frail, clinically significant renal impairment), or patients in whom hypoglycaemic episodes may have devastating effects (bus drivers), newer anti-diabetic agents may be a justifiable alternative option.

Author:

Thrasher J; Daniels K; Patel S; Whetteckey J; Woerle H-J

Title:

Efficacy and safety of linagliptin in black/African American patients with type 2 diabetes: A 6-month, randomized, double-blind, placebo-controlled study

The sodium-glucose co-transporter 2 inhibitor empagliflozin improves diabetic complications in the streptozotocin T1DM model by interfering with glucotoxicity and rescue of beta-cell function

Source:

ATVB Toronto, CA, May 1-3, 2014

Author:

Wu N; Yu X; Greene M; Oderda G

Title:

Evaluation of the prevalence of chronic kidney disease and rates of oral antidiabetic prescribing in accordance with guidelines and manufacturer recommendations in type 2 diabetic patients within a long-term care setting

To date, only limited data are available on the effects of pretreatment with novel oral anticoagulants in the event of traumatic brain injury (TBI). We determined intracerebral hemorrhage volume and functional outcome in a standardized TBI model in mice treated with warfarin or dabigatran. Additionally, we investigated whether excess concentrations of dabigatran could increase bleeding and whether this was preventable by using prothrombin complex concentrate (PCC). C57 mice were treated orally with warfarin or dabigatran; sham-treated mice served as controls. Effective anticoagulation was verified by measurement of international normalized ratio and diluted thrombin time, and TBI was induced by controlled cortical impact (CCI). Twenty-four hours after CCI, intracerebral hemorrhage volume was larger in warfarin-pretreated mice than in controls (10.1±4.9 vs 4.1±1.7 .L; analysis of variance post hoc P=0.001), but no difference was found between controls and dabigatran-pretreated mice (5.3±1.5 .L). PCC applied 30 minutes after CCI did not reliably reduce intracerebral hemorrhage induced by excess dabigatran concentration compared with saline (10.4±11.2 vs 8.7±7.1 .L). Our data suggest pathophysiological differences in TBI occurring during warfarin and dabigatran anticoagulation. The reduced hemorrhage formation under dabigatran therapy could present a safety advantage compared with warfarin. An excess dabigatran concentration, however, can increase hemorrhage.Journal of Cerebral Blood Flow & Metabolism advance online publication, 19 February 2014; doi:10.1038/jcbfm.2014.31.

In the kidney, the sodium-glucose cotransporters SGLT2 and SGLT1 are thought to account for >90 and ~3% of fractional glucose reabsorption (FGR), respectively. However, euglycemic humans treated with an SGLT2 inhibitor maintain an FGR of 40-50%, mimicking values in Sglt2 knockout mice. Here, we show that oral gavage with a selective SGLT2 inhibitor (SGLT2-I) dose dependently increased urinary glucose excretion (UGE) in wild-type (WT) mice. The dose-response curve was shifted leftward and the maximum response doubled in Sglt1 knockout (Sglt1-/-) mice. Treatment in diet with the SGLT2-I for 3 wk maintained 1.5- to 2-fold higher urine glucose/creatinine ratios in Sglt1-/- vs. WT mice, associated with a temporarily greater reduction in blood glucose in Sglt1-/- vs. WT after 24 h (-33 vs. -11%). Subsequent inulin clearance studies under anesthesia revealed free plasma concentrations of the SGLT2-I (corresponding to early proximal concentration) close to the reported IC50 for SGLT2 in mice, which were associated with FGR of 64 ± 2% in WT and 17 ± 2% in Sglt1-/-. Additional intraperitoneal application of the SGLT2-I (maximum effective dose in metabolic cages) increased free plasma concentrations ~ 10-fold and reduced FGR to 44 ± 3% in WT and to - 1 ± 3% in Sglt1-/-. The absence of renal glucose reabsorption was confirmed in male and female Sglt1/Sglt2 double knockout mice. In conclusion, SGLT2 and SGLT1 account for renal glucose reabsorption in euglycemia, with 97 and 3% being reabsorbed by SGLT2 and SGLT1, respectively. When SGLT2 is fully inhibited by SGLT2-I, the increase in SGLT1-mediated glucose reabsorption explains why only 50-60% of filtered glucose is excreted.

Linagliptin for patients aged 70 years or older with type 2 diabetes inadequately controlled with common antidiabetes treatments: A randomised, double-blind, placebo-controlled trial

Source:

Lancet 382 (9902), 1413-1423 (2013)

Abstract:

Background: A substantial proportion of patients with type 2 diabetes are elderly (=65 years) but this group has been largely excluded from clinical studies of glucose-lowering drugs. We aimed to assess the effectiveness of linagliptin, a dipeptidyl peptidase-4 inhibitor, in elderly patients with type 2 diabetes. Methods: In this randomised, double-blind, parallel-group, multinational phase 3 study, patients aged 70 years or older with type 2 diabetes, glycated haemoglobin A1c (HbA1c) of 7.0% or more, receiving metformin, sulfonylureas, or basal insulin, or combinations of these drugs, were randomised (by computer-generated randomisation sequence, concealed with a voice-response system, stratifi ed by HbA1c level [<8.5% vs =8.5%] and insulin use [yes vs no], block size four) in a 2:1 ratio to once-daily oral treatment with linagliptin 5 mg or matching placebo for 24 weeks. Investigators and participants were masked to assignment throughout the study. The primary endpoint was change in HbA1c from baseline to week 24. This trial is registered with ClinicalTrials.gov, number NCT01084005. Findings: 241 community-living outpatients were randomised (162 linagliptin, 79 placebo). Mean age was 74.9 years (SD 4.3). Mean HbA1c was 7.8% (SD 0.8). At week 24, placebo-adjusted mean change in HbA1c with linagliptin was -0.64% (95% CI -0.81 to -0.48, p<0.0001). Overall safety and tolerability were much the same between the linagliptin and placebo groups; 75.9% of patients in both groups had an adverse event (linagliptin n=123, placebo n=60). No deaths occurred. Serious adverse events occurred in 8.6% (14) of patients in the linagliptin group and 6.3% (fi ve) patients in the placebo group; none were deemed related to study drug. Hypoglycaemia was the most common adverse event in both groups, but did not differ between groups (24.1% [39] in the linagliptin group, 16.5% [13] in the placebo group; odds ratio 1.58, 95% CI 0.78-3.78, p=0.2083). Interpretation: In elderly patients with type 2 diabetes linagliptin was efficacious in lowering glucose with a safety profi le similar to placebo. These fi ndings could inform treatment decisions for achieving individualised glycaemic goals with minimal risk in this important population of patients.

Kidney fibrosis is the final common of all progressive chronic kidney diseases, of which diabetic nephropathy is the leading cause. Endothelial-to-mesenchymal transition (EndMT) has emerged as one of the most important origins of matrix-producing fibroblasts. Dipeptidyl peptidase-4 (DPP-4) inhibitors have been introduced into the market as anti-diabetic drugs. Here, we found that the DPP-4 inhibitor linagliptin cured kidney fibrosis in type 1 diabetic mice without altering their blood glucose levels. Streptozotocin-induced diabetic CD1 mice exhibited severe kidney fibrosis and strong immunoreactivity for DPP-4 24 weeks after the onset of diabetes. At 20 weeks after the onset of diabetes, the mice were treated with linagliptin for 4 weeks. Linagliptin-treated diabetic mice exhibited an amelioration of kidney fibrosis and restored normal kidney structure. These anti-fibrotic effects of linagliptin were associated with the inhibition of EndMT. The therapeutic effects of linagliptin on diabetic kidneys were associated with the suppression of profibrotic programs, as assessed by mRNA microarray analysis. We found that the induction of DPP-4 observed in diabetic kidneys may be associated with suppressed levels of microRNA29s in diabetic mice. Using cultured endothelial cells, we found that linagliptin inhibited TGF.2-induced EndMT and the motility of fibroblast-like EndMT cells. These results indicate the possible novel pleiotropic action of linagliptin to restore normal kidney function in diabetic patients with renal impairment.

Author:

Wüster T; Kaczybura N; Brückner R; Keller M

Title:

Synthesis of enantiomerically pure model compounds of the glucose-6-phosphate-T1-translocase inhibitors kodaistatins A-D. Inferences with regard to the stereostructure of the natural products

OBJECTIVE: Hypertensive patients with metabolic risk factors, including obesity, diabetes, and metabolic syndrome, often require a combination of antihypertensive agents to achieve blood pressure (BP) targets. This article considers the evidence supporting telmisartan/amlodipine combination therapy for the treatment of hypertension in patients with metabolic risk factors. METHODS: Clinical trials of telmisartan/amlodipine at doses of 40-80.mg/5-10.mg (T40-80/A5-10) in free, fixed-dose and single-pill combinations were identified through electronic searches (MEDLINE and congress abstracts) up to and including June 2012, and from the Boehringer Ingelheim (BI) trial database. All identified trials were reviewed for data on hypertensive patients with obesity, diabetes, or both. Post-hoc subgroup analyses were carried out using the BI database to determine the relevant information if it was not previously reported. RESULTS: Thirteen clinical trials including 6886 patients were identified with data relevant for inclusion in this review. The telmisartan/amlodipine combination allowed a high proportion of hypertensive patients with metabolic conditions to achieve BP targets, particularly among patients who had previously failed to achieve BP targets with monotherapy. BP reductions and goal rate achievement were similarly high among patients with and without the presence of metabolic risk factors. BP reductions were maintained throughout the 24.h dosing period, and 24.h goal rates were obtained in a high proportion of patients. Particularly large reductions in BP with telmisartan/amlodipine were recorded among patients with severe hypertension (systolic BP .180.mmHg). CONCLUSIONS: The results of this post-hoc analysis further support the ability of the telmisartan/amlodipine combination to effectively reduce BP in hypertensive patients with obesity, diabetes, or metabolic syndrome, enabling the majority of patients to achieve target BP. This combination is also well tolerated, and may be considered a suitable option for these added-risk hypertensive patients.

Direct n-glucuronidation of the CYP3A probe midazolam: Effects of a CYP3A and dual CYP3A/UGT1A4 inhibitor in healthy volunteers.

Source:

Clin Pharmacol Ther 93 (1), 11 (2013)

Abstract:

BACKGROUND: Midazolam is a widely used FDA-recommended CYP3A probe substrate. The primary route of metabolism, 1'- hydroxylation, was shifted to direct N-glucuronidation, mediated by UGT1A4, under CYP3A-inhibited conditions in human hepatocytes Translation to the clinic was evaluated by comparing the effects of the CYP3A inhibitor, indinavir, and the dual CYP3A/UGT1A4 inhibitor, ritonavir, on the pharmacokinetics of midazolam and metabolites in healthy volunteers METHODS: Participants (n=12) enrolled in a prospective, randomized, open-label, three-way crossover study. They received indinavir (800 mg q8h x 3) or ritonavir (300 mg q12h x 2) with a snack or snack alone (control). Midazolam syrup (2.5 mg) was administered 1h after the second dose of inhibitor. Plasma was collected (0-12h) post-midazolam administration and analyzed for midazolam and metabolites by LC/MS/MS. Pharmacokinetics were evaluated via noncompartmental analysis (Phoenix WinNonlin v.6.3) RESULTS: Relative to control, both inhibitors increased midazolam and midazolam N-glucuronide geometric mean AUC0-12h by .apprx.8-fold (p<0.0001) and .apprx.4-fold (p<0.0001), respectively. Indinavir decreased 1'-hydroxymidazolam AUC0-12h by 42% (p=0.02); ritonavir decreased 1'-hydroxymidazolam concentrations to below limits of quantification Indinavir and ritonavir decreased 1'-hydroxymidazolam glucuronide AUC0-12h by 54% (p<0.0001) and 85%, respectively CONCLUSION: The unanticipated increase in midazolam N-glucuronide AUC0-12h in the presence of ritonavir indicated no inhibition of UGT1A4 at the dose tested. Consistent with in vitro observations, ritonavir was a more potent inhibitor of CYP3A in vivo than indinavir. The decrease in 1'-hydroxymidazolam exposure by both inhibitors was accompanied by an increase in midazolam N-glucuronide exposure, suggesting that midazolam metabolism was diverted partly from the CYP3A- to the UGT1A4-mediated pathway under CYP3A-inhibited conditions.

AIM: To investigate potential drug-drug interactions between empagliflozin and warfarin. METHODS: Healthy subjects (n.=.18) received empagliflozin 25.mg qd for 5.days (treatment A), followed by empagliflozin 25.mg qd for 7.days (days 6-12) with a single 25.mg dose of warfarin on day 6 (treatment B), and a single 25.mg dose of warfarin alone (treatment C), in an open-label, crossover study. Subjects received treatments in sequence AB_C or C_AB with a washout period of .14.days between AB and C or C and AB. RESULTS: Warfarin had no effect on empagliflozin area under concentration-time curve or maximum plasma concentration at steady-state (AUC(.,ss) or C(max,ss)): geometric mean ratios (GMRs) (90% confidence intervals [CI]) were 100.89% (96.86, 105.10) and 100.64% (89.79, 112.80), respectively. Empagliflozin had no effect on AUC from 0.h to infinity (AUC(0-.)) or C(max) for R- or S-warfarin (GMRs [90% CI] for AUC(0-.): 98.49% [95.29, 101.80] and 95.88% [93.40, 98.43], respectively; C(max): 97.89% [91.12, 105.15] and 98.88% [91.84, 106.47], respectively). Empagliflozin had no clinically relevant effects on warfarin's anticoagulant activity (international normalised ratio [INR]) (GMR [95% CI] for peak INR: 0.87 [0.73, 1.04]; area under the effect-time curve from 0 to 168.h: 0.88 [0.79, 0.98]. No drug-related adverse events were reported for empagliflozin after monotherapy or combined administration. The combination of empagliflozin and warfarin was well tolerated. CONCLUSIONS: No drug-drug interactions were observed between empagliflozin and warfarin, indicating that empagliflozin and warfarin can be co-administered without dosage adjustments of either drug.

Strategies for a comprehensive understanding of metabolism by aldehyde oxidase.

Source:

Expert Opin Drug Metab Toxicol 9 (2), 153-168 (2013)

Abstract:

Introduction: Aldehyde oxidase (AO) is a drug-metabolizing molybdo-fla-voenzyme with profound species differences in expression and activity toward various substrates. The contribution of this enzyme to the metabolism and clearance of heterocyclic-containing xenobiotics appears to have increased in recent years, but has not always been identified prior to clinical studies. As a result, drug candidates have been negatively impacted in development.Areas covered: This review provides the most recent in vitro and in vivo strategies for the drug metabolism-pharmacokinetic (DMPK) scientist. The review details approaches for confirmation of AO as an operable metabolic pathway, estimating clearance and fraction of total metabolism, and identification of an appropriate surrogate species for human AO activity for evaluating safety of clinically relevant metabolites.Expert opinion: As the role of AO in metabolism of new drug molecules continues to emerge, it is critical that DMPK scientists have the most updated methodologies to enable formulation of a thorough experimental plan to understand the potential implications of this metabolic pathway. Whether it is higher-than-expected clearance, contributing to an unfavorable half-life, or the formation of an AO-derived disproportionate human metabolite (DHM), such a plan would serve to minimize complications or attrition of drug candidates due to unforeseen issues in the clinic.

A novel model-based meta-analysis to indirectly estimate the comparative efficacy of two medications: An example using DPP-4 inhibitors, sitagliptin and linagliptin, in treatment of type 2 diabetes mellitus

Source:

BMJ Open 3 (3) art.no. e001844 (2013)

Abstract:

Objectives: To develop a longitudinal statistical model to indirectly estimate the comparative efficacies of two drugs, using model-based meta-analysis (MBMA). Comparison of two oral dipeptidyl peptidase (DPP)-4 inhibitors, sitagliptin and linagliptin, for type 2 diabetes mellitus (T2DM) treatment was used as an example. Design: Systematic review with MBMA. Data sources: MEDLINE, EMBASE, http://www. ClinicalTrials.gov, Cochrane review of DPP-4 inhibitors for T2DM, sitagliptin trials on Food and Drug Administration website to December 2011 and linagliptin data from the manufacturer. Eligibility criteria for selecting studies: Double-blind, randomised controlled clinical trials, =12 weeks' duration, that analysed sitagliptin or linagliptin efficacies as changes in glycated haemoglobin (HbA1c) levels, in adults with T2DM and HbA1c >7%, irrespective of background medication. Model development and application: A Bayesian model was fitted (Markov Chain Monte Carlo method). The final model described HbA1c levels as function of time, dose, baseline HbA1c, washout status/duration and ethnicity. Other covariates showed no major impact on model parameters and were not included. For the indirect comparison, a population of 1000 patients was simulated from the model with a racial composition reflecting the average racial distribution of the linagliptin trials, and baseline HbA1c of 8%. Results: The model was developed using longitudinal data from 11 234 patients (10 linagliptin, 15 sitagliptin trials), and assessed by internal evaluation techniques, demonstrating that the model adequately described the observations. Simulations showed both linagliptin 5 mg and sitagliptin 100 mg reduced HbA1c by 0.81% (placebo-adjusted) at week 24. Credible intervals for participants without washout were-0.88 to-0.75 (linagliptin) and-0.89 to-0.73 (sitagliptin), and for those with washout,-0.91 to-0.76 (linagliptin) and-0.91 to-0.75 (sitagliptin).

Genetics of canine diabetes melitus: Are the diabetes susceptibility genes identified in humans involved in breed susceptibility to diabetes melitus in dogs?

Source:

Vet J (Lond) 195 (2), 139-147 (2013)

Abstract:

Diabetes mellitus is a common endocrinopathy in companion animals, characterised by hyperglycaemia, glycosuria and weight loss, resulting from an absolute or relative deficiency in the pancreatic hormone insulin. There are breed differences in susceptibility to diabetes mellitus in dogs, with the Samoyed breed being overrepresented, while Boxers are relatively absent in the UK population of diabetic dogs, suggesting that genetic factors play an important role in determining susceptibility to the disease. A number of genes, linked with susceptibility to diabetes mellitus in humans, are associated with an increased risk of diabetes mellitus in dogs, some of which appear to be relatively breed-specific. Diabetes mellitus in dogs has been associated with major histocompatibility complex (MHC) class II genes (dog leucocyte antigen; DLA), with similar haplotypes and genotypes being identified in the most susceptible breeds. A region containing a variable number of tandem repeats (VNTR) and several polymorphisms have been identified in the canine insulin gene, with some alleles associated with susceptibility or resistance to diabetes mellitus in a breed-specific manner. Polymorphisms in the canine CTLA4 promoter and in other immune response genes are associated with susceptibility to diabetes mellitus in a number of pedigree breeds. Genome wide association studies are currently underway that should shed further light on the genetic factors responsible for the breed profile seen in the diabetic dog population.